Anatomy and Physiology XXVI Flashcards
What signs/ symptoms are present in open/wide angle glaucoma?
Painless, peripheral then central vision loss usually with increased IOP. Optic disk atrophy with cupping occurs (p.439)
What conditions are associated with open/ wide angle glaucoma?
Increased age, african american race, family history, elevated IOP (p.439)
What type of glaucoma is most common in the US?
Open/ Wide angle glaucoma (p.439)
What are the primary and secondary causes of open/wide angle glaucoma?
Primary cause is unclear; secondary causes include uveitis, trauma, corticosteroids, and vasoproliferative retinopathy that can block or decrease outflow at the trabecular meshwork (p.439)
What is closed/ narrow angle glaucoma?
Enlargement or forward movement of the lens against the central iris leads to obstruction of normal aqueous flow through the pupil. This causes fluid buildup behind the iris, pushing the peripheral iris agains the cornea and impeding flow through the trabecular network (p.439)
What are the two forms of closed/narrow angle glaucoma?
Chronic closure and acute closure (p.439)
What is chronic closure closed/ narrow angle glaucoma?
Usually asymptomatic closed/ narrow angle glaucoma with damage to the optic nerve and peripheral vision (p.439)
What is acute closure closed/narrow angle glaucoma?
A true opthalmic emergency where increased IOP pushes the iris forwards closing the angle abruptly (p.439)
What symptoms are characteristic of acute closure closed/ narrow angle glaucoma?
Very painful, sudden vision loss, halos around lights, rock-hard eye, frontal headache (p.439)
What drug is contraindicated in suspected acute closure closed/narrow angle glaucoma and why?
Epinephrine due to its mydriatic effect (p.439)
What is the primary difference between acute and chronic closed/narrow angle glaucoma?
Acute is an opthalamic emergency and is very painful; chronic is typically painless and is not emergent (p.439)
What are cataracts?
Painless, often bilateral opacification of the lens causing a decrease in vision (p.439)
Name 10 risk factors for cataracts.
Age, smoking, EtOH, excessive sunlight, prolonged corticosteroid use, classic galactosemia, galactokinase deficiency, diabetes (sorbitol), trauma, infection (p.439)
What is papilledema?
Optic disk swelling (usually bilateral) due to increased intracranial pressure (p.439)
What findings are noted on fundoscopic exam in a patient with papilledema?
An enlarged blind spot and elevated optic disk with blurred margins (p.439)
What cranial nerve innervates the lateral rectus muscle?
CN VI (p.439)
What cranial nerve innervates the superior oblique muscle?
CN IV (p.439)
To what extraoccular muscle does the trochlea attach/ activate?
Superior oblique muscle (p.439)
Name the six extraoccular muscles.
Superior Oblique, Inferior oblique, Medial Rectus, Lateral Rectus, Superior Rectus, Inferior Rectus (p.439)
When adducted, the superior oblique muscle moves in what directions?
It abducts, intorts, and depresses (p.439)
What signs and symptoms are associated with CN III damage?
The eye looks down and out; ptosis, pupillary dilation, loss of accomodation (p.439)
What signs and symptoms are associated with CN IV damage?
The eye moves upwards, particularly with contralateral gaze and ipsilateral head tilt (p.439)
What signs and symptoms are associated with CN VI damage?
Medially directed eye that cannot abduct (p.439)
A patient with CN IV damage typically reports problems doing what?
Going down stairs (p.439)
To test the function of the superior rectus muscle, how do you direct the patient to move his/her eye?
Have the patient try to look up from the abducted position (p.440)
